The field of the invention relates to the field of remote controlled vehicles and, in particular, to steering mechanisms and remote controllers for toy vehicles and other small motorized devices.
There is a long-felt need for electronic control circuits for remote controlled toy vehicles having the capability to control numerous vehicle functions and that are inexpensive to fabricate. Remote control circuits are housed in a hand controller having function keys that enable an individual to control a vehicle. In response to a function key selection, the circuits transmit control signals from the hand controller to control the operation of the vehicle. The number of vehicle functions to be remotely controlled continues to increase as the number of vehicle functions, e.g., steering, direction, speed, lights, sound, etc., increases with newer toys. As the number of functions increase, the control circuits for remotely controlled toy vehicles have become complex and more expensive. The cost of control circuits is often a substantial portion of the entire manufacturing cost of the vehicle. The market for toy vehicles is notoriously competitive and price sensitive. It is economically impracticable to substantially increase the sales price for remote controlled toys to pay for expensive control electronics. Accordingly, a significant cost and market advantage can be gained by reducing the cost of the control electronics in a remote controlled toy vehicle. The present invention provides a low cost integrated circuit (IC) controller for remote control vehicles.
The present invention includes a IC remote control circuit for a hand controller that includes a toggle switch for reducing the number of function keys, control lines, memory and transmitted signals needed to control a vehicle. The hand controller has a small group of function keys, e.g., four keys labeled k1, k2, k3 and k4. These function keys are used to control all remotely controllable functions of the vehicle. The vehicle may have more controllable functions, such as eight controllable functions, than the number of function keys, such as four function keys, on the hand controller. To handle a large number of controllable functions, each of the function keys alternatively controls two (or more) functions of the vehicle. A toggle switch on the hand controller configures the function keys to alternatively control different vehicle functions. In particular, the toggle switch(es) on the hand controller determines which of two (or more) vehicle functions that will be controlled by each function key.
The toggle switch determines whether the small group of function keys on the hand controller performs a first set of functions (function nos. 1 to 4), or a second set of functions (function nos. 5 to 8). These key function groups may include, for example, a first set of four functions for left and right steering of the vehicle, and forward and reverse directions; and a second set of four functions which include a slow vehicle speed, fast speed, on/off lights and on/off horn. Where the hand controller has four function keys and one toggle function, the controller will emit five signalsxe2x80x94four signals each corresponding to one of the four function keys and a fifth (and possible a sixth) signal for the toggle key. While the actual number of function keys will depend on the total number of controllable vehicle functions, it is preferable that the number of functions keys be fewer than the number of functions and that the number of functions be an integer multiple of the number of function keys.
The receiving controller on the vehicle includes an antenna to receive the control signals transmitted by the hand controller over a wireless or wired link to the vehicle. The receiving controller in the vehicle processes the signals received from the hand controller and converts the signals into vehicle control signals that operate and control the vehicle. The signals transmitted by the hand controller include a unique control signal for each function key, and for the toggle switch(es). The receiving controller detects each of the signals and recognizes them as a specific function key signal or a toggle switch(es) signal.
The receiving controller receives and decodes the toggle switch signal and the function key signals. When received by the vehicle controller, the toggle switch signal is applied to control a function group selection circuit in the vehicle. The function group selection circuit controls which one of two groups of vehicle control functions are active at any given period of time. Accordingly, the toggle switch signal causes to be active either a first group of vehicle control functions or a second group of vehicle control functions, depending on the toggle switch setting on the hand controller. The first group of vehicle control functions may be vehicle left and right steering and vehicle forward and reverse drive directions. The second group of vehicle control functions may be up and down bucket movement, and up and down backhoe movement. Thus, depending on the setting of the toggle switch (and, hence, the toggle switch signal) the active functions being controlled on the vehicle may be steering (left, right, forward and backward) or movements of bucket and backhoe.
The function key signals received by the vehicle correspond to each of the function keys on the hand controllers. Each function key signal may be applied in the vehicle to activate one of two functions, wherein one function is in the first group of vehicle control functions and the second function is in the second group of vehicle control functions. However, two vehicle functions are not activated simultaneously when a function key control signal is received. Rather, one vehicle function is activated which corresponds to both the function key signal and the group of control functions selected by the received toggle switch signal.
Accordingly, the toggle switch enables a hand controller with only four function keys to control eight vehicle functions. Several advantages flow from using the toggle switch to alternatively configure the function keys to activate different vehicle functions. These advantages for a hand controller having four function keys and a toggle switch include: (i) that the controller IC need have only five or six input ports (pins) (four for the function keys, and one or two for the toggle switch(es)), rather than eight ports that would otherwise be needed for eight functions; (ii) the hand controller need have only four function keys, rather than eight; (iii) only five or six control signals need be stored in the IC for each of the function keys and toggle switch(es), and (iv) the memory needed in the IC for generating the control signals is minimized because of the reduced number of control signals. These advantages allow for the use of a less expensive controller IC provide cost savings in manufacture of a remote control toy vehicle. Similar advantages are gained because the controller IC for the vehicle also need only have five or six input ports and only five output ports.
A further aspect of the present invention is a center steering controller formed as an integrated circuit (IC) in the vehicle that controls the steering gear box of a remote controlled toy vehicle. The center steering controller includes an IC processor that generates left and right turn output signals by activating left and right turn signal lines between the controller and an electrically-operated steering gear box for the toy vehicle. The IC also automatically generates a center steering command when no left or right turn signals are being received by the vehicle. The IC processor is controlled by left and right turn signals received from a radio (RF) receiver, and by a center detector circuit. A mechanical center steering controller is disclosed in commonly-assigned U.S. Pat. No. 6,170,354 (U.S. application Ser. No. 09/357,808), filed Jul. 20, 1999, and incorporated by reference here.
The central detector circuit monitors the left and right signal control lines between the integrated circuit and steering gear box. The central detector remains inactive if either signal line is active for left and right turning. If no signal is present on the left and right signal lines, the central detector generates a signal to the processor to cause the gear box to center the steering wheels and drive the vehicle in a straight (or near center) direction. The operator sets the central detector to steer the vehicle in a straight direction, or to steer the vehicle slightly to the left or right (such as if the user wants the vehicle to turn in a large radius circle when no turn signal is being received). An advantage of the automatic central steering control circuit is its simplicity in requiring only left and right turn signals to output left and right signals to the gear box. A center position signal is automatically generated by the central detector and processor when there is no right or left turn signal. Another advantage is that the automatic central steering control circuit has minimal components and, thus, has a manufacturing cost advantage.